

ABSTRACT

The present invention provides a process for detecting the presence or absence of at least one specific nucleic acid sequence in a sample or distinguishing between two different nucleic acid sequences in said sample, wherein each nucleic acid sequence to be detected consists of two separate strands, which process comprises amplifying the specific sequence or sequences (if present) by   (a) treating the sample with one oligonucleotide primer for each of the two strands of each different specific nucleic acid sequence being detected under hybridizing conditions such that for each strand of each different sequence being detected an extension product of each primer is synthesized which is complementary to each nucleic acid strand, wherein said primers are selected so as to be substantially complementary to each strand of each specific sequence such that the extension product synthesized from one primer, when it is separated from its complement, serves as a template for synthesis of an extension product of the other primer; (b) treating the product of step (a) under denaturing conditions to separate the primer extension products from their templates; (c) treating the product of step (b) with oligonucleotide primers such that a primer extension product is synthesized using each of the single strands produced in step (b) as a template; and detecting the thus amplified sequence or sequences (if present).



